"In the summer there's a little more of a casual attitude and with the heat a little more flesh exposed," explains Margaret Fiester, operations manager for the Alexandria, Virginia-based SHRM's HR Knowledge Center.

That's why it's a good idea for employers to establish guidelines and define what "business casual" means, says Fiester.

It may mean one thing at one company and something else at another, depending on corporate culture, she explains, noting some companies have a much more relaxed attitude.

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"At the beginning of every summer or when the weather warms up, we send out a fun reminder," says Ann Marie Theologitis, talent management specialist at ClearVision, a designer and distributor of eyewear and sunwear. "Last year we did one around the TV show 'What Not to Wear.' "

The company also does an email, and reminders at company meetings. Its guidelines state clothing should be professional and clean and not expose an employee's abdomen, chest, back or undergarments. So that means no halter tops, tube tops, spaghetti straps, or camisoles. Shorts and skirts should fall to the knee, and flip-flops and baseball caps are not allowed.

"It's important to set guidelines so there's some sort of common understanding of what our expectations are," says Theologitis.

Know your values. When setting your guidelines, be clear on your personal and professional "brands," says Mila Grigg, CEO of MODA Image and Brand Consulting in Nashville, Tennessee. Specifically, establish three to five brand attributes you want people to associate with you and your company. For instance, if an attribute is integrity, then visible undergarments would not be something you'd want your firm associated with, she notes. Remember when choosing clothing that "professional is the foundation to your brand," Grigg says.

It's good to have a formal policy in place before summer begins to avoid any confusion, says Doug Rowe, a partner in the labor and employment practice group at Certilman Balin Adler & Hyman LLP in East Meadow.

A formal policy, while not a legal requirement, can help protect a company's image, help it comply with health and safety laws and prevent discrimination claims (ie. sexual harassment), he notes.

Be evenhanded. The dress code should apply to all employees, barring special circumstances such as a disability that prevents an individual from adhering to a particular dress requirement, Rowe says. It also should not conflict with an employee's national origin or religious practices.

If an employee doesn't adhere to the dress code, give a warning first about what's not appropriate, he says. If clothing is really inappropriate, tell the employee to change before considering other discipline.

Be consistent and lead by example. "Don't ignore the dress code yourself," says Fiester.